RESUMO
The use of artificial lighting during the incubation phase is a tool that has been studied with the aim of increasing the production rates and hatchability. Using this, this study aims to investigate the effects of the luminous incidence of white and red monochromatic light on the production and metabolism of broiler chicks subjected to low temperatures. A total of 315 eggs of Ross 708 heavy breeders were used. The eggs were distributed randomly, with 35 eggs per tray, totaling 105 eggs per incubator. The treatments were the following: incubation without the use of light; the use of white monochromatic light; and the use of red monochromatic light. The lamps used were of the LED type. The samples were distributed in the factorial completely randomized experimental design with position effect on the tray. Candling, egg weighing, calculating the probability of survival and egg weight loss were performed. Temperatures were recorded using a thermographic camera. At birth, three chicks per tray were euthanized for evaluation: weight with and without yolk residue, gastrointestinal tract biometry, and blood and liver biochemistry. Analyses were performed using the R computational program. It was observed that there was a significant effect of the treatments on the levels of calcium, phosphorus, cholesterol, amylase, glucose, urea and glutamate pyruvate transaminase on the biochemical profile of the blood and on the thermographic temperatures of the eggs; the experiment was kept at low temperatures resulting in thermal stress, with an average temperature of 34.5 °C. Therefore, the use of red and white monochromatic light in the artificial incubation process for brown-colored eggs is not recommended, because in the post-hatching phase, it promoted the metabolism dysregulation on the blood biochemical profile to control the differentiation in the wavelength of traditional incubation.
RESUMO
Glycerin contributes to the animal's energy metabolism as an important structural component of triglycerides and phospholipids. The present study was carried out to evaluate the effect of replacing corn with 0, 5, 10, and 15% of glycerin in terms of performance, digestibility, carcass yield, relative weights of gastrointestinal tract (GIT) organs, and nutrient metabolism. Four hundred chickens (40.0 g ± 0.05 g) were distributed in a completely randomized design with four treatments and five replicates. Growth parameters were measured at 7, 14, 21, and 42 days. Digestibility of crude protein and fat, carcass yield, relative weights of GIT organs, and biochemical blood profile were measured. The results were subject to an analysis of variance by Tukey's HSD test (p > 0.05). The inclusion of 5%, 10%, or 15% of glycerin did not influence performance or affect the crude protein and fat digestibility in broilers (p > 0.05) when compared to that of the basal (0%) diet. Similarly, the supplementation of glycerin levels showed no significant influence (p > 0.05) on the relative GIT organ weights, carcass yield, or nutrient metabolism. Thus, we concluded that glycerin may be included in the broilers' diets in rations of up to 15%.
RESUMO
The objective of this experiment was to evaluate the effects of a diet containing canthaxanthin and 25-hydroxycholecalciferol (25-OH-D3) on the production and reproductive performances of Cobb 500 broiler breeders aged 53 to 61 weeks. The study included 36,000 Cobb 500 female and 3,600 male broiler breeders aging 51 weeks. The birds were housed in three poultry houses divided into four plots, totaling 12 experimental units each containing 3,000 females and 300 males. The birds received the following treatments: control diet (without the studied additives) or the control diet with the addition of 60mg kg-1feed of 25-(OH)-D3 and canthaxanthin feed (6mg of canthaxanthin and 2,760,000IU of 25-(OH)-D3 per kg of feed) per the supplier's recommendations. The experimental design used was a randomized complete block design with two treatments and six replicates. The results were subjected to analysis of variance followed by the F-test. The treatments had no effect on egg production, usability of eggs and number of incubatable eggs per bird housed. The inclusion of canthaxanthin and 25-(OH)-D3 in the diet reduced embryonic mortality while increasing egg yolk pigmentation, hatching percentage, and number of viable chicks produced per bird. Therefore, the use of 60mg kg-1of 25-(OH)-D3 plus canthaxanthin is recommended in the diet of Cobb 500 broiler breeders aging 53 to 61 weeks to improve important reproductive traits that have great economic impacts on poultry farms.
O objetivo deste experimento foi avaliar dietas contendo Cantaxantina e 25-hidroxicolecalciferol (25-OH-D3) sobre o desempenho produtivo e reprodutivo de matrizes de corte da linhagem Cobb 500, de 53 até 61 semanas de idade. Foram utilizadas 36.000 fêmeas e 3.600 machos com 51 semanas de idade, reprodutores de corte Cobb 500. As aves foram alojadas em três aviários divididos em 4 parcelas, totalizando 12 unidades experimentais, cada uma contendo 3.000 fêmeas e 300 machos. As aves foram submetidas aos seguintes tratamentos: dieta controle (sem os aditivos em estudo) ou dieta com adição de 60mg kg-1de ração de 25-(OH)-D3 e Cantaxantina (6mg de cantaxantina e 2.760.000UI de 25-(OH)-D3 por kg de ração), conforme recomendações do fornecedor. O delineamento experimental utilizado foi em blocos casualizados, com dois tratamentos e seis repetições. Os resultados foram submetidos à análise de variância e posteriormente aplicou-se o teste F. Não houve efeito dos tratamentos sobre as variáveis produção de ovos, aproveitamento de ovos e número de ovos incubáveis por ave alojada. A inclusão de Cantaxantina e de 25-(OH)-D3 na dieta reduziu a mortalidade embrionária e aumentou a pigmentação da gema dos ovos, o percentual de eclosão e o número de pintos viáveis produzidos por ave. Portanto, recomenda-se a utilização de 60mg kg-1de 25-(OH)-D3 mais Cantaxantina na dieta de matrizes de corte da linhagem Cobb 500, de 53 a 61 semanas de idade, para melhorar importantes características reprodutivas que têm grande impacto econômico para as empresas avícolas.
